The invention relates to a stacking device for plate-like objects, and in particular for titer plates or the like, which includes a magazine for holding a stack of the titer plates, a support plate or the like which can be moved between an upper and a lower limit point, a clamping device for clamping the titer plates in the magazine, and at least one spring for biasing the clamping device against the titer plates.
In medical laboratory technology, for example, the Elisa process is used to measure antigens and/or antibodies (enzyme linked immunosorbent assay). For example, in order to measure antigens, antibodies are first absorbed on the titer plate; the titer plate is then washed; and in a subsequent process step, a test liquid containing the antigen is admixed. The next step includes a washing after which enzyme-marked specific antibodies are put on the titer plate. The titer plate is washed again, whereafter a substrate for the enzyme is admixed. Actual measurement of the antigens and/or antibodies is performed in a photometer.
For use of either the photometer or the washing device, it is necessary to have the titer plates unstacked and fed individually thereto.
Once the titer plates leave either the photometer or washing device, it is then necessary for the titer plates to be stacked again.
During the stacking and unstacking process, the fact that the dimensions of titer plates are not completely uniform, that is, that the individual plates may differ in thickness, in width or in the fact that a plate may or may not have an additional lateral edge, has been demonstrated to create a problem with respect to holding the plates.
Prior art stacking devices have attempted to overcome this problem by adjusting the device to the specific dimensions of each titer plate.